Bound, adhesively united shell filling



June 27, 1967 H' RUSSELL BOUND, ADHESIVELY UNITED SHELL FILLING 2 Sheets-Sheet 1 Filed 001;. 50, 1963 INVENTOR. FRANK H RUSSELL ATTORNEYS June 27, 1967 F. H. RUSSELL 3,327,956

BOUND, ADHESIVELY UNITED SHELL FILLING Filed Oct. 30, 1963 2 Sheets-Sheet 86 L as INVENTOR. FRANK H RUSSELL ATTORNEYS United States Patent I 3,327,956 BOUND, ADHESIVELY UNITED SHELL FILLING Frank H. Russell, Andover, Mass., assignor to Bolton- Emerson, Inc, Lawrence, Mass., a corporation of Massachusetts Filed Oct. 30, 1963, Ser. No. 320,135 6 Claims. (Cl. 241-299) This invention relates to an improved, preassembled shell filling or lining for truncated conical refiners of the Jordan engine type.

It has heretofore been proposed, as in US. Patent 2,165,947, to Stuck of July 11, 1939, to provide a glued Jordan lining, which has been subjected to tremendous pressure in a truncated conical mold during the setting of the adhesive, thereby compacting the fibres of the wood separators beyond their elastic limit. However, such glued Jordan linings are not believed to be in general use in the trade. This may be for the reason that while wood is the least costly material for separators, it is also the weakest part of the assembly and may fracture under strains occurring after molding, during shipment and installation in a mill Jordan.

It is the principal object of this invention to achieve the advantages of a low cost, adhesively united Jordan shell filling, formed of full shell length metal knives and substantially uncompacted wood separators, while also assuring that the filling will survive intact and undamaged until installed in. a paper mill Jordan.

Another object of the invention is to provide an adhered Jordan shell filling, including full length, uncompacted wood separators, the full length filling being pro vided with an exterior wound, binder or tape, adhered to the exterior face of the filling, but easily severed before installation.

A further object of the invention is to provide a unitary, full length, unsplit Jordan shell lining formed of two half truncated conical sections adhered to aech other, the bent knives and bent uncompleted, wood separators being also adhered to each other but without such bonding pressure as will damage the separators or squeeze out the adhesive.

Still another objectof the invention is to provide an accurately sized, full length truncated conical shell filling for a paper refiner, for-med of a pair of accurately sized, full length, half sections of adhered knives and uncompacted, wood separators, the sections being adhered to each other under heat and low pressure to avoid changes in dimensions of the filling.

Other objects and advantages of the invention will be apparent from the claims, the description of the drawings and from the drawings, in which FIGURE 1 is a side elevation, in section, of one half filling section being formed into a unit;

FIGURE 2 is an end view in section on line 22 of FIGURE 1;

FIGURE 3 is a perspective view of the two pre-assembled, full length, half filling sections prior to final assembly;

FIGURE 4 is a side elevation on a reduced scale in section of the two half sections being adhered into a complete shell lining.

FIGURE 5 is a side elevation of the completed filling wound with a strong adhesive binder, or tape, and

FIGURE 6 is an end View in section on line 66 of FIGURE 5.

As shown in FIGURES l and 2, the improved shell filling of the invention is formed of conventional bent metal knives 20 and bent wood separators 21, which preferably are coextensive in length with the Jordan shell, rather than being the conventional one-third length re- Patented June 27, 1967 quiring three separate fillings to fill the shell. Unlike the glued Jordan lining of the abovementioned Stuck Patent 2,165,947, wherein the knives and separators are assembled in a truncated conical mold of short axial length, in this invention the filling, or lining, is assembled in a full length, half truncated conical mold, or jig 22. It is therefore possible to handle the unusually long bent knives and separators and to place them in accurate position within the mold 22 through the wide opening 23, this being difficult to accomplish through the circular end opening of a truncated conical mold.

The truncated conical half mold 22 is of predetermined interior dimensions, exactly equal to the corresponding dimensions of the Jordan engine shell for which the filling is being made. Mold 22 includes the skin 24 of sheet material reinforced by the U shaped frame members 25 at the large end and 26 at the small end, there being integral base pieces 27 for supporting the mold several inches above the level of the floor 28. 29 is an intermediate U-shaped frame member.

One full shell length, half truncated conical filling section, 30 or 31, is assembled at a time in the opentopped, half mold 22, the first step being the scribing of a heavy marker line 32 down the longitudinal centre line of the inner face 33 of the bottom of the skin 24. A mold release coating, of any suitable well known type is then applied to the inner face 33. High strength bonding film or paste adhesive, for example the product designated A.F.l1l of Minnesota Mining and Manufactur ing Company is then applied to the opposite side faces 34 and 35 of each knife 20, this material requiring no primer and tacking to metal surfaces at ambient temperatures. The layer, or film, of the high strength adhesive is designated 36 and 37 and is thermosetting and free of volatile by-products during cure thereby permitting low pressure bonding.

Each adhesive layer or film such as 36 is supported by a protective liner on each side when manufactured, the liners forming a tape which is cut to the length of the knife 20. One liner is tripped off, the exposed film applied to the knife and the tape pressed on with a rubber roller to roll out entrapped air. The tape is applied to both faces 34 and 35 of the knives 20, and the first knife is placed in the half mold 22 parallel to the scribed line 32 to align the half filling section. The remaining liners are then removed from the adhesive films 36 and 37 and alternate wood separators 21 and knives 20 are assembled from the bottom of the mold up the sides 38 and 39 to fill the half mold and form the accurate half truncated conical filling section 30. Cheek pieces 41 and 42 are added to form fiat surfaces 43 and 44 so that the plates 45 and 46, backed by springs 47 adjustable by bolts 48 may apply the preferred pressure of about 10 p.s.i. to the adhesive bond areas during the curing cycle. The frame members 25 and 26 each include elongated slots 49 for vertical adjustment of bolts 51 which carry the backing elements 52 and 53 upon which the spring pressed plates 45 and 46 are mounted.

Heating element 55 is then installed longitudinally in the centre of the mold and the mold covered with the heat insulated box 56, the latter having the outlet 57. Preferably the heating element 55 comprises the central support 58, passing through the end apertures 59 and 60 in the removable ends 62 and 63, of box 56, and four radiant heaters 64, 65, 66, and 67, arranged to direct heat outwardly from each quadrant toward the inner face of the half section and mold. The radiant heaters may be of the Chromalox type made by Wiegand Co., Pittsburgh, Pa., and a damper 68 is provided to control ventilation in the oven. The strip heaters 64, 65, 66 and 67 raise the temperature within the insulated box to a J minimum of 250 deg. F. which is maintained for one hour to thoroughly cure the thermosetting adhesive layers 36 and 37 between the side faces 33 and 34 of each knife 20 and the side faces 69 and 70 of each separator 21.

At the end of the one hour curing period, the half filling section 30 is an integral, full shell length, unit and the box 56 and heating elements 55 are removed to allow the unit to cool, whereupon it is removed from the mold. The half section 31 is assembled and cured in the same manner.

The two half filling sections 30 and 31 are then assembled together in upright position and adhesive film 71, identical with the films 36 and 37, is applied to each joint 72 in the same manner as described above. The large ends 73 and 74 of the half sections are down and resting on a suitable support such as the floor 28.

Truncated conical molds 76 and 77, each of which is of the exact inside dimensions desired for the filling product, are lowered over the outside of the two half sections to clamp the sections together at the joint 72 with predetermined low pressure created by the weight of the molds. The molds settle by their own weight on the assembly, as shown in FIGURE 4, the lower mold 76 being supported just above the floor and the upper mold 77 being supported by its end ring 78, on the ends of the knives and separators, at the small ends 79 and 80 of the half sections.

Heating element 55 is then lowered through the aperture 81 of end ring 78, and through the small ends of the filling, down along the longitudinal centre line until the end of the central support, or shaft, 58 rests on the floor 28. The insulated box 56, plus an added section 83 is then mounted around the filling and molds and heat of 300 deg. F. applied for one hour. The entire assembly is thus recured into an adhesively united assembly 84, with the joints 72 firmly bonding the half sections together. The insulated box 56, added section 83 and heating element 55- are then removed and the assembly 84 permitted to cool.

The final, and critical step in producing a commercially acceptable, adhesively united, truncated conical, shell filling is the wrapping of a high tensile strength binder strand 86 around the exterior face 87 of the assembly 84. Preferably the binder strand 86 is a strong adhesive tape having a fibre glass backing 88 and an adhesive layer 89, the tape being about three quarters of an inch wide and about one thirty-second of an inch thick. As shown in FIG. the binder 86 is wrapped around the small end at 91, the large end at 92 and the central portion 93, in at least six encircling convolutions which are helical in order not to overlap each other. The resultant binder layer is thus of a single, uniform thickness which increases the outside diameter by two-thirty-seconds of an inch, the binder layer being easily severable just prior to insertion of the filling into the shell, or, if desired, remaining on the shell as a permanent part thereof during use in the Jordan engine.

The filling of the invention is vulnerable to accidental stresses and strains from the time of removal from the mold to the time of insertion in the Jordan and the weakest component of the filling is probably the uncompacted fibrous structure of the wood separators. The adhesive binder Wrapping relieves the load on the wood separators during transportation, handling and installation without danger of slippage of the binder toward the small end of the filling and without tie or clip connections which would create high spots on the outside preventing a close fit within the Jordan. The entire outside face 87 can be covered with a single, continuous, helically wound adhesive tape binder, to provide a non-slip jacket of tape, if desired, the wood separators being able to swell and expand within the Jordan in the usual manner, since the tape layer overlies the inner face of the shell and expansion would be circumferential and inward to tighten the knives. However, the spaced zones of six convolutions have been found to take less time and to adequately contain the filling under normal wear and tear.

A suitable binder 86 has been found to be Minnesota Mining and Mfg. Co.s filament tape #325, wide.

I claim:

1. A unitary, full length, unsplit, bodily transportable filling for the shell of a tuncated conical pulp refiner, said filling comprising a full length, truncated conical shell filling assembly of alternate, full shell length, metal knives and woodseparators, the fibrous structure of said wood being in substantially natural, uncompacted condition, each knife having a thermoset adhesive film on each opposite side face thereof adhesively uniting the said side face to the side face of the adjacent wood separator,

and a high tensile strength binder strand tightly wrapped around, and encircling a substantial area of, the exterior face of said assembly at spaced distances along the full length thereof from one end to the other end, said binder strand confining said full length assembly and relieving the load on said uncompacted, wood separators when said filling is not mounted within a mold or shell.

2. A filling as specified in claim 1 wherein said high tensile strength binder strand is a narrow fibre-glass tape of uniform thickness wrapped helically around said assembly in single layer convolutions.

3. A filling as specified in claim 1 wherein said high tensile strength binder strand includes an adhesive and is adhered to the truncated conical exterior face of said assembly for avoiding slippage.

4. A filling as specified in claim 1 wherein said binder strand is an easily severable adhesive tape, comprising a fibre glass filament backing with an adhesive layer thereon, said adhesive layered tape being adhered for at least six helical convolutions around said full length assembly at the large end, the small end and the middle of said assembly.

5. A filling as specified in claim 1 wherein said assembly consists of two full length preformed half sections, adhesively united into said truncated conical shell filling assembly.

6. A full shell length, bodily transportable, unsplit filling for the shell of a Jordan engine, said filling comprising two full shell length half sections of alternate, adhesively united bent full shell length bent Wood separators, the wood of said separators having a substantially uncompacted fibrous structure and said full shell length, said half sections being adhesively united into a unitary, truncated conical shell filling assembly and a strong binding tape tightly encircling the exterior of said assembly and adhesively united to the exterior face thereof for confining said assembly until installed in the shell of a Jordan engine.

References Cited UNITED STATES PATENTS 2,029,123 1/ 1936 Stuck 29428 2,165,947 7/ 1-939 Stuck 24l--299 2,650,185 8/1953 Larson ..156-313 ROBERT C. RIORDON, Primary Examiner.

D. KELLY, Assistant Examiner. 

1. A UNITARY, FULL LENGTH, UNSPLIT, BODILY TRANSPORTABLE FILLING FOR THE SHELL OF A TUNCATED CONICAL PULP REFINER, SAID FILLING COMPRISING A FULL LENGTH, TRUNCATED CONICAL SHELL FILLING ASSEMBLY OF ALTERNATE, FULL SHELL LENGTH, METAL KNIVES AND WOOD SEPARATORS, THE FIBROUS STRUCTURE OF SAID WOOD BEING IN SUBSTANTIALLY NATURAL, UNCOMPACTED CONDITION, EACH KNIFE HAVING A THERMOSET ADHESIVE FILM ON EACH OPPOSITE SIDE FACE THEREOF ADHESIVELY UNITING THE SAID SIDE FACE TO THE SIDE FACE OF THE ADJACENT WOOD SEPARATOR, AND A HDIGH TENSILE STRENGTH BINDER STRAND TIGHTLY WRAPPED AROUND, AND ENCIRCLING A SUBSTANTIAL AREA OF, THE EXTERIOR FACE OF SAID ASSEMBLY AT SPACED DISTANCES ALONG THE FULL LENGTH THEREOF FROM ONE END TO THE OTHER END, SAID BINDER STRAND CONFINING SAID FULL LENGTH ASSEMBLY AND RELIEVING THE LOAD ON SAID UNCOMPACTED, WOOD SEPARATORS WHEN SAID FILLING IS NOT MOUNTED WITHIN A MOLD OR SHELL. 